Download The Coriolis force acts perpendicular to the

The Coriolis force acts perpendicular to the
pressure gradient force. The pressure gradient
force is perpendicular to an isobar. The higher
the pressure gradient force, the more is the
velocity of the wind and the larger is the
deflection in the direction of wind. As a result of
these two forces operating perpendicular to each
other, in the low-pressure areas the wind blows
around it. At the equator, the Coriolis force is
zero and the wind blows perpendicular to the
isobars. The low pressure gets filled instead of
getting intensified. That is the reason why tropical
cyclones are not formed near the equator.
Pressure and Wind
The velocity and direction of the wind are the
net result of the wind generating forces. The
winds in the upper atmosphere, 2 - 3 km above
the surface, are free from frictional effect of the
surface and are controlled mainly by the
pressure gradient and the Coriolis force. When
isobars are straight and when there is no
friction, the pressure gradient force is balanced
by the Coriolis force and the resultant wind
blows parallel to the isobar. This wind is known
as the geostrophic wind